Of all the suspensions of disbelief you need to buy into a modern superhero movie, the source of Captain America’s strength maybe needs the least scientific wiggle room.

In my latest Because Science, I’m digging into the science of Cap’s super-soldier serum. Using modern genetics and chemistry, a gene-editing formula that was light-activated could in fact boost muscle growth and the amount of oxygen your blood can ferry around your body, for example. Bouncing a vibranium shield around five surfaces before returning perfectly to your hand? That’s a whole other episode.